/* teach - veilige rolvoorbeeldweergave voor systeemmanagers.
   Alleen de clientinterface en zichtbare menu's veranderen. De sessiecookie,
   currentUser en serverautorisatie blijven altijd van de systeemmanager. */
"use strict";

(function(){
  const roleRow=document.getElementById("superViewRole");
  const roleSeg=document.getElementById("segViewRole");
  const banner=document.getElementById("rolePreviewBanner");
  const bannerLabel=document.getElementById("rolePreviewLabel");
  const resetButton=banner.querySelector("button");
  const ROLE_KEYS={
    super:"vwRoleSystem",admin:"vwRoleAdmin",teacher:"vwRoleTeacher",
    parent:"vwRoleParent",pupil:"vwRolePupil"
  };
  let renderSequence=0;

  const isSystemManager=()=>!!currentUser&&currentUser.role==="super";
  const roleLabel=role=>T(ROLE_KEYS[role]||ROLE_KEYS.super);

  function storedRole(){
    try{
      const value=localStorage.getItem("teach.superViewRole");
      return VIEW_ROLES.includes(value)?value:"super";
    }catch(e){return"super";}
  }
  function storeRole(role){
    try{localStorage.setItem("teach.superViewRole",role);}catch(e){}
  }
  function previewNotice(text){
    const note=document.createElement("aside");
    note.className="role-preview-note";
    const strong=document.createElement("strong");
    strong.textContent=T("vwPreview")+": ";
    note.append(strong,document.createTextNode(text));
    return note;
  }
  function clearPreviewSurface(){
    renderSequence++;
    document.body.classList.remove("role-preview-active","role-preview-parent","role-preview-pupil");
    banner.hidden=true;
    if(isSystemManager()){
      stopPupilView();
      stopParentView();
    }
  }
  function syncControls(){
    const enabled=isSystemManager();
    roleRow.hidden=!enabled;
    const role=enabled?activeRole():"super";
    roleSeg.querySelectorAll("button").forEach(button=>{
      const selected=button.dataset.role===role;
      button.classList.toggle("active",selected);
      button.setAttribute("aria-pressed",String(selected));
    });
    banner.hidden=!enabled||role==="super";
    bannerLabel.textContent=enabled&&role!=="super"?roleLabel(role):"";
  }
  async function renderPreviewSurface(){
    const sequence=++renderSequence;
    if(!isSystemManager()){clearPreviewSurface();syncControls();return;}
    const role=activeRole();
    document.body.classList.remove("role-preview-active","role-preview-parent","role-preview-pupil");
    stopPupilView();
    stopParentView();
    if(role==="parent"){
      document.body.classList.add("role-preview-active","role-preview-parent","parent-mode");
      renderParentView([]);
      const inner=parentView.querySelector(".parent-inner");
      if(inner)inner.prepend(previewNotice(T("vwParentPreview")));
      parentView.querySelectorAll("button,input,select,textarea").forEach(control=>{control.disabled=true;});
    }else if(role==="pupil"){
      document.body.classList.add("role-preview-active","role-preview-pupil","pupil-mode");
      const snapshot=serializeBoard();
      await renderPupilWidgets(snapshot.widgets||[],"kijken",true);
      if(sequence!==renderSequence)return;
      pupilView.prepend(previewNotice(T("vwPupilPreview")));
    }
    syncControls();
  }
  function chooseRole(role){
    if(!isSystemManager()||!VIEW_ROLES.includes(role))return;
    setActiveViewRole(role);
    storeRole(role);
    updateUserUI();
    document.dispatchEvent(new CustomEvent("userchange"));
  }

  roleSeg.querySelectorAll("button").forEach(button=>{
    button.addEventListener("click",()=>chooseRole(button.dataset.role));
  });
  resetButton.addEventListener("click",()=>chooseRole("super"));
  document.addEventListener("userchange",()=>{
    if(isSystemManager()){
      const saved=storedRole();
      if(activeRole()!==saved)setActiveViewRole(saved);
    }else{
      setActiveViewRole("super");
    }
    syncControls();
    renderPreviewSurface();
  });
  document.addEventListener("langchange",()=>{
    syncControls();
    if(isSystemManager()&&["parent","pupil"].includes(activeRole()))renderPreviewSurface();
  });
  syncControls();
})();